基于熔融盐辅助废弃塑料同步碳化-功能化制备超级电容器碳基材料的研究

The project is focused on the basic scientific research about the preparation of carbon materials for supercapacitor with waste plastic carbonizing in the molten salt system. Started with the chemical composition, structure, and the characteristics of molten salt of the waste plastic, the carbon materials with different pore size distribution can be prepared through the optimization of waste plastic type, the ratio of molten salt between waste plastic, heating temperature and carbonization time. At the same time, the carbonization mechanism of different types of plastics in the molten salt system can be further revealed. The synchronous carbonization and heteroatomic doping modification will be achieved by changing the composition of the molten salt, which is also helpful to reveal the effect of different heteroatom modification for the capacitive performance. The influence of surface condition (electrical conductivity, wettability) and capacitance performances of the conductive ceramic phase modified carbon materials can be measured through adding metal salts in the molten salt. Based on this project, it is promising to build a method to prepare structure and performance-controlled plastic waste carbon materials with large quantities and low cost through molten salt auxiliary synthesis. In this way, it will reliably provide theoretical and technical support for the design and preparation of waste plastic carbon materials with super performances.

本项目针对熔融盐辅助碳化处理废弃塑料制备超级电容器碳基材料的基础科学问题展开研究。从废弃塑料的化学组成与结构、熔融盐特性两方面入手，通过优化废弃塑料种类、与熔融盐的比例、反应温度、时间等条件制备出孔径分布可调的碳材料，解析不同塑料种类在熔融盐体系中的碳化机理；通过改变熔融盐组成达到同步碳化以及杂原子原位掺杂改性的目的，阐释杂原子掺杂改性对于电容性能的作用机制；通过在熔融盐体系中引入金属盐组分，一步构筑导电陶瓷相改性的废弃塑料基碳材料，探讨改性后对于碳材料表面状况及电容性能的影响规律，最终建立结构、性能可控的废弃塑料基碳材料的大批量、低成本熔融盐辅助制备方法，为高性能废弃塑料基碳材料的设计和制备研究提供可靠的理论和技术保障。

本项目选用适当的前驱体（如废弃塑料、秸秆、豆腐粉末、面粉等），开展了盐辅助碳化方法制备超级电容器碳基材料的相关研究。通过借鉴黑火药的组成，利用在熔融盐体系中引入硝酸盐作为活化剂制备出孔径分布可调的碳材料。在此基础之上，通过改变熔融盐种类，实现了具有三维纳米带结构的碳材料的自组装；利用面粉制品加工过程中使用小苏打作为活化剂，提出一种化学发泡活化制备多孔碳的新方法，解析了其分步活化的机制；通过浸渍重结晶的方式在碳布表面引入功能性盐，实现碳布表面的凿孔活化并同步杂原子原位掺杂改性的目的，阐释杂原子掺杂改性对于电容性能的作用机制；通过在石墨烯气凝胶中引入赝电容组分，探讨其组成-结构-性能三者之间作用规律，最终建立结构、性能可控的碳基材料的大批量、低成本盐辅助制备方法，本项目的研究成果为开发兼具高能量密度、高功率密度以及低成本的超级电容器具有借鉴作用。